This invention relates to the art of drain cleaning apparatus and, more particularly, to improvements in portable drain cleaning apparatus of the character wherein a drain cleaning snake is manually advanced through the apparatus into a drain or sewer line and is then rotated for the drain cleaning snake to clear an obstruction encountered in the line.
Portable drain cleaning machines or apparatus of the character to which the present invention is directed are well known and, generally, comprise a housing structure supporting a coaxial arrangement of shaft components through which a drain cleaning snake is manually fed and which includes a clutching arrangement for intermittently engaging and rotating the snake in conjunction with a drain cleaning operation. The clutching arrangement includes radially expandable and contractible clutch elements located axially between and coaxial with clutch actuating components of the apparatus and which clutch actuating components are relatively axially displaceable toward and away from one another to respectively achieve contracting and expanding displacement of the clutch elements relative to the snake. Most often, one of the clutch actuating components is axially fixed and the other is axially displaceable toward and away therefrom by means of a manually operable lever arrangement. The clutch actuating components are rotatable and the clutch is axially captured therebetween for rotation therewith, and the clutch actuating components and clutch are rotated by a drive motor and a drive coupling arrangement between the motor and one of the clutch actuating components. Such drain cleaning apparatus is portable and, generally, is provided with a handle by which the apparatus can be carried by an operator from one location to another. In use, a drain cleaning snake is manually inserted through the apparatus and into a drain to be cleaned. If the drive motor is operating, the clutch and clutch actuating components rotate relative to the snake, whereby the latter can be manually advanced through the apparatus and into the drain until an obstruction is encountered. The operating lever is then displaced relative to the housing for the clutch to engage and rotate the snake and, in connection with dislodging or clearing the obstruction, the lever can be released to disengage the clutch from the snake, whereupon the operator can manually feed the snake further into the drain and then displace the operating lever to again cause rotation of the snake relative to the apparatus.
While drain cleaning apparatus of the foregoing character heretofore available serves its intended purpose with respect to performing drain cleaning operations, there are a number of disadvantages attendant to the construction and operation of the apparatus. In this respect, for example, the clutch operating arrangements are structurally complex, and the structural interrelationships between the latter and the drive transmission as well as the housing by which the latter are supported render maintenance and/or replacement operations both time consuming and complex and, thus, undesirably expensive. More particularly in this respect, access to the clutch and clutch actuating components as well as the transmission components most often requires a time consuming disassembly of the housing, and then a further time consuming manipulation and/or disassembly of the components parts in the housing to achieve the release of the clutch unit, clutch actuating components and/or transmission components. Following a removal of one or more of the latter parts for maintenance and/or replacement, a time consuming reassembly is required to place the apparatus back into condition for use.
A further disadvantage resides in the fact that such drain cleaning machines heretofore available require either a replacement of the clutch unit for the apparatus to accommodate snakes having different diameters, or the use of a structurally complex collet insert arrangement for the latter purpose such as shown for example in U.S. Pat. No. 4,447,926 to Rothenberger. As mentioned above, removal and replacement of the clutch unit is a difficult and time consuming operation, and a requirement of a collet insert adds to the structural complexity of a machine as well as requiring an additional part or parts for use therewith as well as the time required for an operator to assemble and/or disassemble an insert relative to the machine.
Another disadvantage relates to the manner in which the apparatus is supported and the manner in which the component parts of the apparatus are supported internally of the apparatus. In this respect, the component parts are both enclosed in and supported by a housing which also serves to support the apparatus on an underlying support surface during use. Thus, the entire housing must have structural integrity, whereby both the cost and weight thereof are undesirably high. Furthermore, the internal structure of the housing required to support and accommodate the component parts of the apparatus is complex which adds further to the cost thereof and to the complexity and cost of performing maintenance and/or replacement operations.